Regulating valve



De- 19, 1944- w. H, nu Bols 2,365,531

' REGULATING VALVE Filed Feb. 2. 1942 2 sheets-sheet 1 ATTO Det; 19,y 1944. w. DU Bmg;v 2,365,531

REGULATIHG VALVE Filed Feb. 2, 1942 2 Sheets-Sheet 2 INVENTOR W/z/A/V/f. 0050/5 BY ATTO NEY Patented Dec. 19, 1944 UNITED STATES PATENT OFFICE BEGULATING VALVE William H. Du Bols. South Bend, Ind., assigner to Bendix Aviation Corporation, South Bend, Ind., a corporation of Delaware Application February 2, 1942, Serial No. 429,147

Claims.

This invention relates to a regulating valve for operating a fluid pressure responsive motor by admitting uid under pressure to said motor.

The object of this invention is to provide an lmproved regulating valve which will be useful in hydraulic or liquid pressure systems and which will have among others the following advantages: effective sealing of the elements which control the alternate connecting of the motor with an inlet or exhaust port; and elimination of substantially all friction from the moving, parts of the regulating valve so that its operation will be highly sensitive and delicately controllable.

Other advantages and desirable features of this invention will become apparent during the course of the following description, reference being had therein to the accompanying drawings in which:

Fig. l is a diagrammatic showing of a fluid pressure system incorporating my improved regulating valve;

Fig. 2 ls a. vertical section taken through the said regulating valve; and

Figs. 3 and 4 are enlarged closeups oi portions of Fig. 2.

A fluid pressure system utilizing my improved regulating valve may comprise, as shown in Fig. l,

a fluid reservoir Il, a pump I2, a conduit I3 con- Y necting the reservoir to the pump, an accumulator I4 for storing fluid under pressure, a conduit i6 connecting the accumulator to the pump, a regulating valve I6, a conduit Il connecting the regulating valve to the accumulator, auid pressure responsive cmotor IB, a conduit I9 connecting the motor I8 to the regulating valve, and a conduit connecting the regulating valve to the reservoir. A pressure relief valve 2l may be connected between the accumulator and the reservoir to allow an escape of pressure iluid from the accumulator if the pressure builds up to a dangerously high point. The motor I8 is shown as being adapted to operate a brake by spreading a pair of brake shoes 22 against a brake drum 23. Obviously a uuid pressure responsive motor of any type might be utilized without departing from the scope of my invention and it might be utilized in accomplishing any function whatsoever, a brake being used in this instance for illustrative purposes only. Further. it should be pointed out that the regulatlng valve I6 will perform it desired function regardless of whether it is connected to an accumulator or is connected directly to a pump, it beingimmaterial whether the pressure iiuid is stored prior to its use in operating the motor or whether the fluid is put under pressure simultaneously with its use in operating the motor.

As is well known in the art, in a iluid pressure system oi the type shown in Fig. 1, the pump I2 draws duid from the reservoir and forces it under pressure into the accumulator, and the iuid re-Y mains under pressure until the operator desires to use the pressure fluid in operating a motor. At that time, by actuating the regulating valve he may permit iluid under pressure to move from the accumulator to the motor and operate the motor. When operation of the motor is no longer desired, release of the regulating valve will allow uid to return from the motor to the reservoir.

A lever 2l may be provided to operate the regulating valve I6. and this lever may either be operated by hand or may be connected to a foot pedal 25. The lever 24 is shown in Fig. 2 pivoted at 26 on an extension 21 protruding from the casing of the regulating valve IB. One end of the lever 2l is adapted to exert force against a push rod 2i which extends into the interior of the regulating valve I6 to set into motion the actuation thereof. The regulating valve has an inlet port 29 connected to the accumulator by conduit I1, an outlet port Il) connected to the motor Il by conduit I9, and an exhaust port Jl connected to the reservoir by conduit 20. Control of communication between the several ports is accomplished con- Jointly by a valve l2, a valve 33, and a piston u. The valve 32 controls communication between accumulator port 29 and motor port 30. said valve 32 comprising (refer to Fig. 4 for a clear disclosure) a valve seat il formed in a hollow insert 36 screwed into the end oi' the regulating valve, a valve head 31 adapted to seat at times at 35 and cut oil' communication between ports 28 and 3D, a valve stem 3l secured to or integral with the valve head Il, an annular ring 39 secured to the stem 38, and a spring lll compressed between the ring 39 and the valve seat 35 to urge the valve head 3l to seat at 35. The valve 33 comprises a valve seat 4| formed on the head of the piston 3l, and a valve element 42 which at times seats at 4I to cut olf communication between ports 30 and Il and which is formed with a well or opening (for clear disclosure sce Fig. 4) into which extends the end of valve stem Il. VAn annular nut M screwed onto the inner end of the hollow insert 36 has a flange 4I which is adapted to at times contact a ilange I6 on the valve element 42 to prevent the said valve element 42 from following wp the piston when the piston moves toward released position. The annular nut Il is also provided with a plurality ofpassages 41 to allow free communication between the interior of the hollow insert Il and the outlet or motor port Il when- .bOlt 50 ever valve 32 is (see Fig. 3) a head ferential surface of which serves to clamp together. A

inner circular the skirt 49 hs its iston assembly guia from motor port 30 to reservoir port 3| is freely allowed through the center oi the said piston assembly 34 except when the valve 33 has seated at 4l on the head 4I.

late 53 movable l2,8 and the piston assembly 34 are compression The spring 54 bears at one end 53 and attheotherendagainst while the spring l5 bears at one end plate 53 and at the other end against the skirt 43 of the piston.

Operation of my improved regulating valve is as follows. When the operator desires to actuate the brakes or other hydraulically controlled device, he causes the lever 24 to move in a counterclockwise direction about its pivot 23 forcing the rod 28 and plate 53 in a direction to compress the springs 54 and 55 and through the said springs exert force on the piston assembly 34 moving it toward the valves 33 and 22. Movement of the piston closes the valve 33 cutting oi communication between motor port 30 and reservoir port 3| and subsequently movement of the piston by pushing Vthe valve element 42 pushes the valve stem 38 and moves valve head 31 from its seat 35 allowing iluid under pressure from the accumulator to enter port 23 and, passing through sport 3c to the hydraulic motor, cause operation or said motor. Fluid under pressure from the accumulator, simultaneously with operating the motor IB exerts a reaction force against the manually operated lever 24 through the medium of the piston head 48. The pressure of the uid exerted against said piston head 48 tends to move the piston against the pressure of the springs 44 and 45, and hen the iluid pressure against the piston head is sufficient, the springs will be compressed sufciently to allow the piston to move toward its released position and allow valve head 31 to seat at 35 and cut off the accumulator or source of iiuid pressure from the motor. In this position, with both valves 32 and 33 closed, the regulating valve is in lapped position. The operator lay exerting further manual pressure on the lever 24 and simultaneously moving said lever 24 in a counterclockwise direction may once again open valve 32 and increase the pressure which is operating motorY I3 by allowing a further now ci pressure uid from the source oi pressure to the motor. Because or the compressbility of springs 54 and 55, the regulating valve may be said to be position sensitive. This is true inasmuch as the operator. in order to increase his manually applied force to thereby allow an increase in the pressure which is operating motor i8, must further compress the springs 54 and 55, and in order to do that, move the lever 24 further and further in a `counterclockwise direction. When manual pressure on lever 24 is diminished or entirely eliminated, the force of pressure iiuid from the pressure source will move the piston amembly 34 in a direction to iirst allow the valve 32 to close cutting oil the ow oi pressure iluid and to subsequently open the valve 33 allowing fluid from the motor` to communicate with the reservoir and release the motor.

Because the pressure operating against the head 4B of the piston is likely to be quite high particularly in a fluid pressure system utilizing .an accumulator for storing fluid under pressure there is a strong tendency for duid to escape past the piston head 43 toward the reservoir port 3| and thus cause substantial loss of effective pressure in the system. Some form of seal must therefore be adopted to prevent the escape of iluld past, the piston head. Use of a, flexible sealing cup of the type generally known in the hydraulic art has been found to create a substantial amount of friction with the walls of the regulating valve. The effect of such friction is to diminish the sensitivity and controllability of the valve. My valve construction accomplishes effective sealing without causing hindering friction. The sealing is accomplished by diaphragm 5l which adequately prevents escape of iluid and does not interfere with free reciprocating movement of the piston assembly 34 inside the valve i6. Further effective sealing is accomplished by the utilization of poppet type valves 32 and 33 which are held on their respective seats, once they have seated, by the pressure of fluid in the accumulator or pressure source, with the result that an exceptionally eiective seal is established and maintained between the various ports of the regulating valve. Particularly in cases where, for example, a brake is to be set for a considerable period of time it is desirable and even necessary to have almost perfect sealing in the regulating valve. Otherwise there will be a gradual leakage of pressure fluid until the pressure source is depleted and the brakes no longer remain applied. This consideration is particularly important in the case of airplanes inasmuch as they often remain stationary for long periods with the parking brakes applied and the supply pumps cut oi. Another advantage of my device worthy of note is that the inlet valve 32 has -been split from the exhaust valve 33 in the sense that the two valves are not rigidly connected. This allows the regulating valve to seek and find a balanced or lapped position with complete accuracy.

Although a single illustrative embodiment of my invention has been described, it is not my intention to limit the scope of my invention to that particular embodiment or otherwise than by the terms of the appended claims.

What I claim is:

l. For a hydraulic pressure system in which the operating liquid is placed under pressure by means other than manual means, a regulating valve comprising a valve body having a. source of pressure port, a motor port and an exhaust port; a piston reciprocable in the valve body having a passage therethrough, and having a head surface subjected to the liquid pressure' prevailing at the motor port; an annular ilexible diaphragm secured to the piston and to the inner wall of the valve body; a compression spring bearing at one end'against the piston on the side opposite the piston head surface; manually operable means for exerting force through the compression spring to move the piston; and an inlet and an outlet valve each comprising a iloating poppen valve element and a. valve seat which make contact with one another along a single circular line, thestem of each of the valve elements being provided with a radial clearance permitting the sealing portion of the valve element to accommodate itself to the valve seat and form a iiuid tight seal, the outlet valve element being caused by initial movement of the piston to close the passage through the piston and thereby cut oil communication between the motor and exhaust ports, and the inlet valve element being caused by subsequent movement of the piston to open commu- -nication between the source of pressure port and the motor port;

2. For a hydraulic pressure system in which the operating liquid is placed under pressure by means other than manual means, a regulating valve comprising a valve body having a source of pressure port, a motor port and an exhaust port a piston reciprocable in the valve body having a passage therethrough, and having a head surface subjected to the liquid pressure prevailing at the motor port; an annular flexible diaphragm secured to the piston and to the inner wall of the valve body; manually operable means for exerting force to move the piston and for receiving the reaction from the liquid pressure acting on the piston head; and an inlet and an outlet valve each comprising a floating poppet valve element and a valve seat which make contact with one another along a single circular line, the stem of each of the valve elements being provided with a radial clearance permitting the sealing portion of the valve element to accommodate itself to the valve seat and form a fluid tight seal, the outlet valve element being caused by initial movement of the piston to close the Lpassage through the piston and' thereby cut off communication between the source of pressure port and outlet valve element when seated being held to its seat by the pressure o! liquid which serves to operate the fluid pressure operable motor, and the inlet valve element being caused by subsequent movement of the piston to open communication between the source of pressure port and the motor port, said inlet valve element when seated being held to its seat by the pressure of liquid from the pressure liquid source.

3. For a hydraulic ,pressure system in which the operating liquid is placed under pressure by` means other than manual means, a regulating valve comprising a valve body having a source of pressure port, a motor port and an exhaust port; a, piston reciprocable in the valve body having a passage therethrough, and having a head surface subjected to the liquid pressure prevailing at the motor port; an annular exible diaphragm secured to the piston and to the inner wall of the valve body and having a substantial portion thereof lying fiat along the outer cylindrical surface of the piston, whereby movement of the piston moves the inner portion of the annular diaphragm longitudinally of the valve body without placing an appreciable tension on the diaphragm; a compression spring ybearing at one end against the piston on the side opposite the piston head surface, said spring being fully extended when the piston is in released position; manually operable means for exerting force through the compression spring to move the piston; an inlet and an outlet valve each comprising a oating poppet valve element and a valve seat which make contact with one another along a single circular line, the outlet valve element being caused by ini. tial movement of the piston to close the passage through the piston and thereby cut off communication between the motor and exhaust ports, and the inlet valve element being caused by subsequent movement of the piston to open communication between the source oi pressure port and the motor port, said piston being substantially free to move from released position until it engages the outlet valve element: a relatively light spring biasing the inlet valve element toward closed position; and a retaining member secured to the valve body and having a :lange thereon to limit movement or the outlet valve element in the direction of the piston, said retaining mem. ber also serving as a guide for said' outlet valve element, said outlet valve element being provided with an opening therein into which is inserted the stern of the inlet valve element, whereby the inlet valve element is guided, said valve elements being slightly spaced irom the respective guiding means, whereby the seating portions of the valve elements are permitted to accommodate themselves to the respective valve seats and form a fluid tight seal.

4. For a hydraulic pressure system in which the operating liquid is placed under pressure by means other than manual means, a regulating valve comprising a valve body having a source of pressure port, a motor port and an exhaust port; a piston reciprocable in the valve body having a passage therethrough, and having a head surface subjected to the liquid pressure prevailing at the motor port; an annular ilexlble diaphragm secured to the piston and to the nner wall of the valve body; a compression spring bearing at one end against the piston on the side opposite the piston head surface, said spring being fully extended when the piston is in released position; manually operable means for exerting force through the compression spring to move the piston; an inlet and an outlet valve each comprising a iioating poppet valve element and a valve seat which make contact with one another along a single circular line, the outlet valve element being caused by initial movement of the piston to close the passage through the piston and thereby cut off communication between the motor and exhaust ports, and the inlet valve element being caused by subsequent movement of the piston to open communication between the source of pressure port and the motor port, said lpiston being substantially free to move from released position until it engages the outlet valve element; a relatively light spring biasing the inlet valve element toward closed position; and a member secured to the valve body and arranged to limit movement of the outlet valve element in the direction of the piston and to guide said outlet valve element, said outlet valve element being provided with an opening therein into which is inserted the stem of the inlet valve element, whereby the inlet valve element ls guided, said valve elements :being slightly spaced from the respective guiding means, whereby the seating portions of the valve elements are permitted to accommodate themselves to the respective valve seats and form a fluid tight seal.

5. For a hydraulic pressure system in which the operating liquid is placed under pressure by means other than manual means, a regulating valve comprising a valve body having a source of pressure port, a motor port and an exhaust port; a piston reciprocable in the valve body having a passage therethrough, and having a head surface subjected to the liquid pressure prevailing at the motor port; an annular flexible diaphragm secured to the piston and to the wall of the valve body: a compression spring bearr` ing at one end against the piston on the side op Patent No. 2,565,551.

WILLIAM E. DU BOIS.

CERTIFICATE 0F CORRECTION.

and thereby cut oi! communication between the motor and exhaust ports, and the inlet valve element being caused by subsequent movement of the piston to open communication between the source of pressure port and the motor port, said piston being substantially free to move from released postion until it engages the outlet valve element; and means for limiting movement of the outlet valve element in the direction of the 10 piston.

WILLIAM H. DU BOIS.

December 19, 19ml..

I It is hereby certified that error appears in this printed specification of the above numbered patent requiring correction as follows: Page l, first column, line M9, for it desired'l read --its desired; page 3, first column, line 55, claim 2, for 'source of pressure port and read --motorandexheuet por-ts, said and that the said Letter Patent should be read this correction therein that the seme may confom to the record of the case in the Patas t Office lsigned and sealed this 12th day er June, A. -D. 1915.

(Seal) Leslie Frazer Acting Commissioner ofPatents.

r` ing at one end against the piston on the side op Patent No. 2,565,551.

WILLIAM E. DU BOIS.

CERTIFICATE 0F CORRECTION.

and thereby cut oi! communication between the motor and exhaust ports, and the inlet valve element being caused by subsequent movement of the piston to open communication between the source of pressure port and the motor port, said piston being substantially free to move from released postion until it engages the outlet valve element; and means for limiting movement of the outlet valve element in the direction of the 10 piston.

WILLIAM H. DU BOIS.

December 19, 19ml..

I It is hereby certified that error appears in this printed specification of the above numbered patent requiring correction as follows: Page l, first column, line M9, for it desired'l read --its desired; page 3, first column, line 55, claim 2, for 'source of pressure port and read --motorandexheuet por-ts, said and that the said Letter Patent should be read this correction therein that the seme may confom to the record of the case in the Patas t Office lsigned and sealed this 12th day er June, A. -D. 1915.

(Seal) Leslie Frazer Acting Commissioner ofPatents. 

